--- /dev/null
+*.so
+*.swp
+*.o
+*.swo
#include <sys/un.h>
#include <sched.h>
#include <fcntl.h>
+#include <poll.h>
#include "marker.h"
#include "tracer.h"
char consumer_stack[10000];
+struct list_head blocked_consumers = LIST_HEAD_INIT(blocked_consumers);
+
static struct ustcomm_app ustcomm_app;
struct tracecmd { /* no padding */
struct ltt_channel_struct *chan;
};
+struct blocked_consumer {
+ int fd_consumer;
+ int fd_producer;
+ int tmp_poll_idx;
+
+ /* args to ustcomm_send_reply */
+ struct ustcomm_server server;
+ struct ustcomm_source src;
+
+ /* args to ltt_do_get_subbuf */
+ struct rchan_buf *rbuf;
+ struct ltt_channel_buf_struct *lttbuf;
+
+ struct list_head list;
+};
+
int consumer(void *arg)
{
int result;
ustcomm_request_consumer(getpid(), "ust");
}
+void process_blocked_consumers(void)
+{
+ int n_fds = 0;
+ struct pollfd *fds;
+ struct blocked_consumer *bc;
+ int idx = 0;
+ char inbuf;
+ int result;
+
+ list_for_each_entry(bc, &blocked_consumers, list) {
+ n_fds++;
+ }
+
+ fds = (struct pollfd *) malloc(n_fds * sizeof(struct pollfd));
+ if(fds == NULL) {
+ ERR("malloc returned NULL");
+ return;
+ }
+
+ list_for_each_entry(bc, &blocked_consumers, list) {
+ fds[idx].fd = bc->fd_producer;
+ fds[idx].events = POLLIN;
+ bc->tmp_poll_idx = idx;
+ idx++;
+ }
+
+ result = poll(fds, n_fds, 0);
+ if(result == -1) {
+ PERROR("poll");
+ return -1;
+ }
+
+ list_for_each_entry(bc, &blocked_consumers, list) {
+ if(fds[bc->tmp_poll_idx].revents) {
+ long consumed_old = 0;
+ char *reply;
+
+ result = read(bc->fd_producer, &inbuf, 1);
+ if(result == -1) {
+ PERROR("read");
+ continue;
+ }
+ if(result == 0) {
+ DBG("PRODUCER END");
+
+ close(bc->fd_producer);
+
+ __list_del(bc->list.prev, bc->list.next);
+
+ result = ustcomm_send_reply(&bc->server, "END", &bc->src);
+ if(result < 0) {
+ ERR("ustcomm_send_reply failed");
+ continue;
+ }
+
+ continue;
+ }
+
+ result = ltt_do_get_subbuf(bc->rbuf, bc->lttbuf, &consumed_old);
+ if(result == -EAGAIN) {
+ WARN("missed buffer?");
+ continue;
+ }
+ else if(result < 0) {
+ DBG("ltt_do_get_subbuf: error: %s", strerror(-result));
+ }
+ asprintf(&reply, "%s %ld", "OK", consumed_old);
+ result = ustcomm_send_reply(&bc->server, reply, &bc->src);
+ if(result < 0) {
+ ERR("ustcomm_send_reply failed");
+ free(reply);
+ continue;
+ }
+ free(reply);
+
+ __list_del(bc->list.prev, bc->list.next);
+ }
+ }
+
+}
+
int listener_main(void *p)
{
int result;
int len;
struct ustcomm_source src;
- result = ustcomm_app_recv_message(&ustcomm_app, &recvbuf, &src, -1);
- if(result <= 0) {
+ process_blocked_consumers();
+
+ result = ustcomm_app_recv_message(&ustcomm_app, &recvbuf, &src, 5);
+ if(result < 0) {
WARN("error in ustcomm_app_recv_message");
continue;
}
+ else if(result == 0) {
+ /* no message */
+ continue;
+ }
DBG("received a message! it's: %s\n", recvbuf);
len = strlen(recvbuf);
struct ltt_channel_buf_struct *lttbuf = trace->channels[i].buf;
char *reply;
long consumed_old=0;
+ int fd;
+ struct blocked_consumer *bc;
- result = ltt_do_get_subbuf(rbuf, lttbuf, &consumed_old);
- if(result < 0) {
- DBG("ltt_do_get_subbuf: error: %s", strerror(-result));
- asprintf(&reply, "%s %ld", "UNAVAIL", 0);
- }
- else {
- DBG("ltt_do_get_subbuf: success");
- asprintf(&reply, "%s %ld", "OK", consumed_old);
- }
-
- result = ustcomm_send_reply(&ustcomm_app.server, reply, &src);
- if(result) {
- ERR("listener: get_subbuf: ustcomm_send_reply failed");
+ bc = (struct blocked_consumer *) malloc(sizeof(struct blocked_consumer));
+ if(bc == NULL) {
+ ERR("malloc returned NULL");
goto next_cmd;
}
+ bc->fd_consumer = src.fd;
+ bc->fd_producer = lttbuf->data_ready_fd_read;
+ bc->rbuf = rbuf;
+ bc->lttbuf = lttbuf;
+ bc->src = src;
+ bc->server = ustcomm_app.server;
- free(reply);
+ list_add(&bc->list, &blocked_consumers);
break;
}
free(channel_name);
free(consumed_old_str);
}
- else if(nth_token_is(recvbuf, "get_notifications", 0) == 1) {
- struct ltt_trace_struct *trace;
- char trace_name[] = "auto";
- int i;
- char *channel_name;
-
- DBG("get_notifications");
-
- channel_name = strdup_malloc(nth_token(recvbuf, 1));
- if(channel_name == NULL) {
- ERR("put_subbuf_size: cannot parse channel");
- goto next_cmd;
- }
-
- ltt_lock_traces();
- trace = _ltt_trace_find(trace_name);
- ltt_unlock_traces();
-
- if(trace == NULL) {
- CPRINTF("cannot find trace!");
- return 1;
- }
-
- for(i=0; i<trace->nr_channels; i++) {
- struct rchan *rchan = trace->channels[i].trans_channel_data;
- int fd;
-
- if(!strcmp(trace->channels[i].channel_name, channel_name)) {
- struct rchan_buf *rbuf = rchan->buf;
- struct ltt_channel_buf_struct *lttbuf = trace->channels[i].buf;
-
- result = fd = ustcomm_app_detach_client(&ustcomm_app, &src);
- if(result == -1) {
- ERR("ustcomm_app_detach_client failed");
- goto next_cmd;
- }
-
- lttbuf->wake_consumer_arg = (void *) fd;
-
- smp_wmb();
-
- lttbuf->call_wake_consumer = 1;
-
- break;
- }
- }
-
- free(channel_name);
- }
+// else if(nth_token_is(recvbuf, "get_notifications", 0) == 1) {
+// struct ltt_trace_struct *trace;
+// char trace_name[] = "auto";
+// int i;
+// char *channel_name;
+//
+// DBG("get_notifications");
+//
+// channel_name = strdup_malloc(nth_token(recvbuf, 1));
+// if(channel_name == NULL) {
+// ERR("put_subbuf_size: cannot parse channel");
+// goto next_cmd;
+// }
+//
+// ltt_lock_traces();
+// trace = _ltt_trace_find(trace_name);
+// ltt_unlock_traces();
+//
+// if(trace == NULL) {
+// CPRINTF("cannot find trace!");
+// return 1;
+// }
+//
+// for(i=0; i<trace->nr_channels; i++) {
+// struct rchan *rchan = trace->channels[i].trans_channel_data;
+// int fd;
+//
+// if(!strcmp(trace->channels[i].channel_name, channel_name)) {
+// struct rchan_buf *rbuf = rchan->buf;
+// struct ltt_channel_buf_struct *lttbuf = trace->channels[i].buf;
+//
+// result = fd = ustcomm_app_detach_client(&ustcomm_app, &src);
+// if(result == -1) {
+// ERR("ustcomm_app_detach_client failed");
+// goto next_cmd;
+// }
+//
+// lttbuf->wake_consumer_arg = (void *) fd;
+//
+// smp_wmb();
+//
+// lttbuf->call_wake_consumer = 1;
+//
+// break;
+// }
+// }
+//
+// free(channel_name);
+// }
else {
ERR("unable to parse message: %s", recvbuf);
}
DBG("just auto connected marker %s %s to probe default", m->channel, m->name);
}
-/* Wake the consumer of a buffer
- *
- * wake_consumer_cb is called in tracing context so it must haste.
- *
- * FIXME: don't do a system call here; maybe schedule work to be done
- * in listener context? Once this is done in listener context, we can
- * check for the return value of send_message_fd and remove the fd if necessary
- *
- * @arg: the buffer
- * @finished: 0: subbuffer full; 1: buffer being destroyed
- */
-
-static void wake_consumer_cb(void *arg, int finished)
-{
- struct ltt_channel_buf_struct *ltt_buf = (struct ltt_channel_buf_struct *) arg;
- int fd = (int)ACCESS_ONCE(arg);
-
- if(!finished) {
- send_message_fd(fd, "consume", NULL);
- }
- else {
- send_message_fd(fd, "destroyed", NULL);
- }
-}
-
static void __attribute__((constructor(101))) init0()
{
DBG("UST_AUTOPROBE constructor");
if(getenv("UST_AUTOPROBE")) {
marker_set_new_marker_cb(auto_probe_connect);
}
-
- relay_set_wake_consumer(wake_consumer_cb);
}
static void fini(void);
struct ltt_channel_struct *channel =
(struct ltt_channel_struct *)buf->chan->private_data;
struct ltt_channel_buf_struct *ltt_buf = channel->buf;
+ int result;
- if(ltt_buf->call_wake_consumer)
- relay_wake_consumer(ACCESS_ONCE(ltt_buf->wake_consumer_arg), 0);
+ result = write(ltt_buf->data_ready_fd_write, "1", 1);
+ if(result == -1) {
+ PERROR("write (in ltt_relay_buffer_flush)");
+ ERR("this should never happen!");
+ }
//ust// atomic_set(<t_buf->wakeup_readers, 1);
}
{
struct ltt_channel_buf_struct *ltt_buf = ltt_chan->buf;
unsigned int j;
+ int fds[2];
+ int result;
ltt_buf->commit_count =
zmalloc(sizeof(ltt_buf->commit_count) * n_subbufs);
local_set(<t_buf->events_lost, 0);
local_set(<t_buf->corrupted_subbuffers, 0);
- ltt_buf->call_wake_consumer = 0;
- ltt_buf->wake_consumer_arg = NULL;
+ result = pipe(fds);
+ if(result == -1) {
+ PERROR("pipe");
+ return -1;
+ }
+ ltt_buf->data_ready_fd_read = fds[0];
+ ltt_buf->data_ready_fd_write = fds[1];
return 0;
}
struct ltt_channel_struct *channel =
(struct ltt_channel_struct *)buf->chan->private_data;
struct ltt_channel_buf_struct *ltt_buf = channel->buf;
+ int result;
buf->finalized = 1;
ltt_force_switch(buf, FORCE_FLUSH);
- relay_wake_consumer(ltt_buf, 1);
+ result = write(ltt_buf->data_ready_fd_write, "1", 1);
+ if(result == -1) {
+ PERROR("write (in ltt_relay_buffer_flush)");
+ ERR("this should never happen!");
+ }
}
static void ltt_relay_async_wakeup_chan(struct ltt_channel_struct *ltt_channel)
static void ltt_relay_finish_buffer(struct ltt_channel_struct *ltt_channel)
{
struct rchan *rchan = ltt_channel->trans_channel_data;
+ int result;
if (rchan->buf) {
struct ltt_channel_buf_struct *ltt_buf = ltt_channel->buf;
ltt_relay_buffer_flush(rchan->buf);
//ust// ltt_relay_wake_writers(ltt_buf);
+ /* closing the pipe tells the consumer the buffer is finished */
+
+ //result = write(ltt_buf->data_ready_fd_write, "D", 1);
+ //if(result == -1) {
+ // PERROR("write (in ltt_relay_finish_buffer)");
+ // ERR("this should never happen!");
+ //}
+ close(ltt_buf->data_ready_fd_write);
}
}
//ust// * writers
//ust// */
//ust// atomic_t wakeup_readers; /* Boolean : wakeup readers waiting ? */
- /* whether or not wake_consumer must be called; must be accessed atomically */
- int call_wake_consumer;
- /* the arg to pass to wake_consumer; must be accessed atomically */
- void *wake_consumer_arg;
+ /* one byte is written to this pipe when data is available, in order
+ to wake the consumer */
+ /* portability: Single byte writes must be as quick as possible. The kernel-side
+ buffer must be large enough so the writer doesn't block. From the pipe(7)
+ man page: Since linux 2.6.11, the pipe capacity is 65536 bytes. */
+ int data_ready_fd_write;
+ /* the reading end of the pipe */
+ int data_ready_fd_read;
} ____cacheline_aligned;
int ltt_do_get_subbuf(struct rchan_buf *buf, struct ltt_channel_buf_struct *ltt_buf, long *pconsumed_old);
int result;
result = send_message_fd(src->fd, msg, NULL);
- if(result) {
+ if(result < 0) {
ERR("error in send_message_fd");
return -1;
}
int fd;
};
+/* ustcomm_server must be shallow-copyable */
struct ustcomm_server {
/* the "server" socket for serving the external requests */
int listen_fd;
struct ustcomm_server server;
};
+/* ustcomm_source must be shallow-copyable */
struct ustcomm_source {
int fd;
void *priv;
#define atomic_long_set atomic_set
#define atomic_long_read atomic_read
-#include "asm.h"
-
//#define __xg(x) ((volatile long *)(x))
#define cmpxchg(ptr, o, n) \
all: ustd
ustd: ustd.c
- gcc -g -Wall -I ../libustcomm -I. -I ../../../../libkcompat -o ustd ustd.c ../libustcomm/ustcomm.c
+ gcc -g -Wall -I ../libustcomm -I. -I ../../../../libkcompat -lpthread -o ustd ustd.c ../libustcomm/ustcomm.c
.PHONY: ustd
#include <sys/shm.h>
#include <fcntl.h>
#include <unistd.h>
+#include <pthread.h>
#include <stdlib.h>
#include <stdio.h>
long consumed_old;
};
-int add_buffer(pid_t pid, char *bufname)
-{
- struct buffer_info *buf;
- char *send_msg;
- char *received_msg;
- int result;
- char *tmp;
- int fd;
-
- buf = (struct buffer_info *) malloc(sizeof(struct buffer_info));
- if(buf == NULL) {
- ERR("add_buffer: insufficient memory");
- return -1;
- }
-
- buf->name = bufname;
- buf->pid = pid;
-
- /* get shmid */
- asprintf(&send_msg, "get_shmid %s", buf->name);
- send_message(pid, send_msg, &received_msg);
- free(send_msg);
- DBG("got buffer name %s", buf->name);
-
- result = sscanf(received_msg, "%d", &buf->shmid);
- if(result != 1) {
- ERR("unable to parse response to get_shmid");
- return -1;
- }
- free(received_msg);
- DBG("got shmid %d", buf->shmid);
-
- /* get n_subbufs */
- asprintf(&send_msg, "get_n_subbufs %s", buf->name);
- send_message(pid, send_msg, &received_msg);
- free(send_msg);
-
- result = sscanf(received_msg, "%d", &buf->n_subbufs);
- if(result != 1) {
- ERR("unable to parse response to get_n_subbufs");
- return -1;
- }
- free(received_msg);
- DBG("got n_subbufs %d", buf->n_subbufs);
-
- /* get subbuf size */
- asprintf(&send_msg, "get_subbuf_size %s", buf->name);
- send_message(pid, send_msg, &received_msg);
- free(send_msg);
-
- result = sscanf(received_msg, "%d", &buf->subbuf_size);
- if(result != 1) {
- ERR("unable to parse response to get_subbuf_size");
- return -1;
- }
- free(received_msg);
- DBG("got subbuf_size %d", buf->subbuf_size);
-
- /* attach memory */
- buf->mem = shmat(buf->shmid, NULL, 0);
- if(buf->mem == (void *) 0) {
- perror("shmat");
- return -1;
- }
- DBG("successfully attached memory");
-
- /* open file for output */
- asprintf(&tmp, "/tmp/trace/%s_0", buf->name);
- result = fd = open(tmp, O_WRONLY | O_CREAT | O_TRUNC, 00600);
- if(result == -1) {
- PERROR("open");
- return -1;
- }
- buf->file_fd = fd;
- free(tmp);
-
- list_add(&buf->list, &buffers);
-
- return 0;
-}
+/* return value: 0 = subbuffer is finished, it won't produce data anymore
+ * 1 = got subbuffer successfully
+ * <0 = error
+ */
int get_subbuffer(struct buffer_info *buf)
{
free(send_msg);
result = sscanf(received_msg, "%as %ld", &rep_code, &buf->consumed_old);
- if(result != 2) {
+ if(result != 2 && result != 1) {
ERR("unable to parse response to get_subbuffer");
return -1;
}
- free(received_msg);
+
+ DBG("received msg is %s", received_msg);
if(!strcmp(rep_code, "OK")) {
DBG("got subbuffer %s", buf->name);
retval = 1;
}
+ else if(nth_token_is(received_msg, "END", 0) == 1) {
+ return 0;
+ }
else {
- DBG("did not get subbuffer %s", buf->name);
- retval = 0;
+ DBG("error getting subbuffer %s", buf->name);
+ retval = -1;
}
+ /* FIMXE: free correctly the stuff */
+ free(received_msg);
free(rep_code);
return retval;
}
return bufc-(const char *)buf;
}
+void *consumer_thread(void *arg)
+{
+ struct buffer_info *buf = (struct buffer_info *) arg;
+ int result;
+
+ for(;;) {
+ result = get_subbuffer(buf);
+ if(result == -1) {
+ ERR("error getting subbuffer");
+ continue;
+ }
+ if(result == 0) {
+ /* this is done */
+ break;
+ }
+
+ /* write data to file */
+ result = patient_write(buf->file_fd, buf->mem + (buf->consumed_old & (buf->n_subbufs * buf->subbuf_size-1)), buf->subbuf_size);
+ if(result == -1) {
+ PERROR("write");
+ /* FIXME: maybe drop this trace */
+ }
+
+ result = put_subbuffer(buf);
+ if(result == -1) {
+ ERR("error putting subbuffer");
+ break;
+ }
+ }
+
+ DBG("thread for buffer %s is stopping", buf->name);
+
+ return NULL;
+}
+
+int add_buffer(pid_t pid, char *bufname)
+{
+ struct buffer_info *buf;
+ char *send_msg;
+ char *received_msg;
+ int result;
+ char *tmp;
+ int fd;
+ pthread_t thr;
+
+ buf = (struct buffer_info *) malloc(sizeof(struct buffer_info));
+ if(buf == NULL) {
+ ERR("add_buffer: insufficient memory");
+ return -1;
+ }
+
+ buf->name = bufname;
+ buf->pid = pid;
+
+ /* get shmid */
+ asprintf(&send_msg, "get_shmid %s", buf->name);
+ send_message(pid, send_msg, &received_msg);
+ free(send_msg);
+ DBG("got buffer name %s", buf->name);
+
+ result = sscanf(received_msg, "%d", &buf->shmid);
+ if(result != 1) {
+ ERR("unable to parse response to get_shmid");
+ return -1;
+ }
+ free(received_msg);
+ DBG("got shmid %d", buf->shmid);
+
+ /* get n_subbufs */
+ asprintf(&send_msg, "get_n_subbufs %s", buf->name);
+ send_message(pid, send_msg, &received_msg);
+ free(send_msg);
+
+ result = sscanf(received_msg, "%d", &buf->n_subbufs);
+ if(result != 1) {
+ ERR("unable to parse response to get_n_subbufs");
+ return -1;
+ }
+ free(received_msg);
+ DBG("got n_subbufs %d", buf->n_subbufs);
+
+ /* get subbuf size */
+ asprintf(&send_msg, "get_subbuf_size %s", buf->name);
+ send_message(pid, send_msg, &received_msg);
+ free(send_msg);
+
+ result = sscanf(received_msg, "%d", &buf->subbuf_size);
+ if(result != 1) {
+ ERR("unable to parse response to get_subbuf_size");
+ return -1;
+ }
+ free(received_msg);
+ DBG("got subbuf_size %d", buf->subbuf_size);
+
+ /* attach memory */
+ buf->mem = shmat(buf->shmid, NULL, 0);
+ if(buf->mem == (void *) 0) {
+ perror("shmat");
+ return -1;
+ }
+ DBG("successfully attached memory");
+
+ /* open file for output */
+ asprintf(&tmp, "/tmp/trace/%s_0", buf->name);
+ result = fd = open(tmp, O_WRONLY | O_CREAT | O_TRUNC, 00600);
+ if(result == -1) {
+ PERROR("open");
+ return -1;
+ }
+ buf->file_fd = fd;
+ free(tmp);
+
+ //list_add(&buf->list, &buffers);
+
+ pthread_create(&thr, NULL, consumer_thread, buf);
+
+ return 0;
+}
+
int main(int argc, char **argv)
{
struct ustcomm_ustd ustd;
/* app loop */
for(;;) {
char *recvbuf;
- struct buffer_info *buf;
- /* 1. check for requests on our public socket */
+ /* check for requests on our public socket */
result = ustcomm_ustd_recv_message(&ustd, &recvbuf, NULL, 100);
if(result == -1) {
ERR("error in ustcomm_ustd_recv_message");
free(recvbuf);
}
-
- /* 2. try to consume data from tracing apps */
- list_for_each_entry(buf, &buffers, list) {
- result = get_subbuffer(buf);
- if(result == -1) {
- ERR("error getting subbuffer");
- continue;
- }
- if(result == 0)
- continue;
-
- /* write data to file */
- //result = write(buf->file_fd, buf->, );
- result = patient_write(buf->file_fd, buf->mem + (buf->consumed_old & (buf->n_subbufs * buf->subbuf_size-1)), buf->subbuf_size);
- if(result == -1) {
- PERROR("write");
- /* FIXME: maybe drop this trace */
- }
-
- result = put_subbuffer(buf);
- if(result == -1) {
- ERR("error putting subbuffer");
- }
- }
}
return 0;